Since all that include/linux/if_ppp.h does is #include <linux/ppp-ioctl.h>,
this replaces the occurrences of #include <linux/if_ppp.h> with
#include <linux/ppp-ioctl.h>.

It also corrects an error in Documentation/networking/l2tp.txt, where
it referenced include/linux/if_ppp.h as the source of some definitions
that are actually now defined in include/linux/if_pppol2tp.h.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds documentation about the L2TPv3 functionality.
Signed-off-by: NJames Chapman <jchapman@katalix.com>
Reviewed-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix various typos in documentation txts.
Signed-off-by: NMatt LaPlante <kernel1@cyberdogtech.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Signed-off-by: NJames Chapman <jchapman@katalix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>